body,html{height:100%}html{display:table;margin:auto}body{display:table-cell;vertical-align:middle}.bg{background-image:url(cool-wallpaper-3.6232bdb7c94b5af09c9b.jpg);height:100%;background-position:center;background-repeat:no-repeat;background-size:cover}#export-file,.custom-file{margin:10px}